备忘录模式

Folgerjun · web-flow · commit faba2e29e9da · 2018-03-12T10:45:08.000+08:00
备忘录模式
diff --git a/java-des/src/com/java/design/memento/Caretaker.java b/java-des/src/com/java/design/memento/Caretaker.java
@@ -0,0 +1,21 @@
+package com.java.design.memento;
+
+/**
+ * 用于保存
+ * 
+ * @author Administrator
+ *
+ */
+public class Caretaker {
+
+	private Memento memento;
+
+	public Memento getMemento() {
+		return memento;
+	}
+
+	public void setMemento(Memento memento) {
+		this.memento = memento;
+	}
+
+}
diff --git a/java-des/src/com/java/design/memento/Memento.java b/java-des/src/com/java/design/memento/Memento.java
@@ -0,0 +1,20 @@
+package com.java.design.memento;
+
+public class Memento {
+
+	private String state;
+
+	public Memento(String state) {
+
+		this.state = state;
+	}
+
+	public String getState() {
+		return state;
+	}
+
+	public void setState(String state) {
+		this.state = state;
+	}
+
+}
diff --git a/java-des/src/com/java/design/memento/MementoPattern.java b/java-des/src/com/java/design/memento/MementoPattern.java
@@ -0,0 +1,29 @@
+package com.java.design.memento;
+
+/**
+ * 备忘录模式 -----> 在不破坏封闭的前提下，捕获一个对象的内部状态，并在该对象之外保存这个状态。这样以后就可将该对象恢复到原先保存的状态
+ * 
+ * @author Administrator
+ *
+ */
+public class MementoPattern {
+
+	public static void main(String[] args) {
+
+		Originator originator = new Originator();
+		originator.setState("在洗澡 ...");
+		originator.showState();
+
+		// 状态进行保存
+		Caretaker caretaker = new Caretaker();
+		caretaker.setMemento(originator.createMemento());
+
+		originator.setState("在吃饭 ...");
+		originator.showState();
+
+		// 重新将状态拿出来
+		originator.setMemento(caretaker.getMemento());
+		originator.showState();
+	}
+
+}
diff --git a/java-des/src/com/java/design/memento/Originator.java b/java-des/src/com/java/design/memento/Originator.java
@@ -0,0 +1,29 @@
+package com.java.design.memento;
+
+public class Originator {
+
+	private String state;
+
+	public String getState() {
+		return state;
+	}
+
+	public void setState(String state) {
+		this.state = state;
+	}
+
+	public Memento createMemento() {
+		return new Memento(state);
+	}
+
+	public void setMemento(Memento memento) {
+
+		state = memento.getState();
+	}
+
+	public void showState() {
+
+		System.out.println(state);
+	}
+
+}
